Question

I can’t find the answer anywhere. It can be done by using condition and throwing exception but is there any other way to do so?

Answer 1

It isn’t clear why you would want a class that cannot be constructed under any circumstances, but you could make all constructors private and provide no implementation for them. This will prevent construction at compile time.

In C++11 you can use delete for all the constructors:

class A
{
 public: // or private, doesn't matter.
  A()=delete;
  A(const A&)=delete;
  A(A&&)=delete;
};